A Spider's Deduction
by SJBell
Summary: S.H.I.E.L.D sends operative agent Natasha Romanoff, codename Black Widow to London to become bodyguard for Sherlock Holmes and John Watson who have captured the unwanted attention of criminal organisation HYDRA. Well, for Sherlock, the attention is indeed welcomed. Obviously.
1. Coffee and Pot Plants

**Here is my first cross-over everyone! I am only posting the first chapter until I complete my other fic. This idea in particular I have had for so long, so I just had to write it down, just to see what people think of it! So let me know what you think and I'll continue writing chapters! **** (Set after the Avengers and before Captain America: The Winter Soldier)**

The Consulting Detective paced around apartment 221B, John Watson was becoming increasingly agitated at Sherlock's constant movement. He often wondered if the man ever stopped to sleep. The phone rang and John answered, "Hello, John Watson speaking", "How's the murder coming along? Development I'm presuming" The ever cheerful Mycroft would often call to pry into the works of Holmes and Watson. "Oh, yes. Right. Murder." Covering the phone with his hand John called across the flat, "Sherlock its Mycroft. He wants to know how the investigation is going." No answer. John threw back his head and groaned, _does the man ever answer?_ Pulling himself from his desk, John shuffled to the lounge area to find Sherlock in all his glory rocking on the lounge in his robe. "Sherlock, Mycroft is on the phone, referring to the murder-" The detective leapt from the lounge, "I've got it dear Watson! By goodness I've got it!" Rolling his eyes, John followed the clever idiot to the kitchen. "This beverage provides an unlimited supply of energy. It has increased my thought process exponentially!" John looked down at the mug of coffee. "Coffee Sherlock? Everyone drinks coffee!" His remark oozed an annoyance. Sherlock laughed, "Ah yes. But not everyone has my intelligence dear Watson!" John sighed.

You would think a year of living with the man, he would've been used to it. There was never any point to argue with him. "Anyways. Mycroft wants to know how the investigation is going." Sherlock whipped his head around, "Bellhop with the wrench in the basement." John just stared into space. "This isn't a game of bloody Cluedo Sherlock, the Ambassador is dead!" Sherlock snatched the phone from Watson and flew back onto the lounge, rolling across to his bookshelf. "Yes Mycroft it was the bellhop, Carew. He had access to Ambassador Alana Graine's room and belongings, along with keys to the basement, janitor's office where he got the murder weapon and trash barges where he dumped the body and said murder weapon. Obviously." Sherlock hung up the phone and John stood there, mouthing the word _obviously. _

The Black Widow followed Agent Coulson through the corridor to the S.H.I.E.L.D Mainframe. Nick Fury held his hands behind his back, "Welcome Agent Romanoff and Agent Coulson." Natasha nodded her head, and Coulson gave a pearly smile. They headed down the stair well where Agent Maria Hill was waiting, punching in the code, the door slid open and they walked in. Fury sat at his desk and Maria left back to the Mainframe. Natasha took a seat and Coulson stood beside the cabinets, fiddling with the files. "Now Agent Romanoff, we have a new assignment for you. Overseas, to London specifically. It's a protection job, and it will be your responsibility to protect and see that no harm will come to who you will be watching over." Nick Fury looked over to Coulson, who had accidently knocked over a pot plant. Clearing his throat he continued, "Yes, Natasha. You will need to be stealthy and keep the subjects from harm. The employer is an old friend of mine, and is counting on your skill." Coulson gleamed impressed with his performance. Fury rolled his eye not covered by a patch. Natasha went from Coulson to Fury, "So who am I protecting?" Leaning forward, Director Nick Fury answered, "The residents of 221B Baker Street, Sherlock Holmes and Doctor John Watson."


	2. Obviously

**I'm going to continue this, because I just can't get the idea out of my mind. I love creating ideas for the interactions between Black Widow and Sherlock, and hopefully you all enjoy it! **

Natasha Romanoff passed through English customs with ease. Coulson's 'friend' had taken care of all the paper work and such, so once the private jet landed, she was cleared to just simply walk through. London was very… Wet. And cloudy. And cold. Natasha wore layers of clothes and her combat boots. Her red curls bounced as she walked out of the airport, where the sleek black car was waiting for her. A man placed her bags in the trunk and opened the door for her. "I hope the flight was comfortable and there was no troubles with customs." The employer, she presumed, sat to her right. "It was fine, thank you. And no trouble." The employer smiled and signalled for the car to go, "221B Baker Street if you please."

John pinched his nose, the rotten stench lingered in the kitchen. "Sherlock you can't keep putting brains in the fridge!" Sherlock pouted his lips, studying the brain on the dining table. "Can you get that off the table! We eat on that!" The Consulting Detective turned the plate, using a knife to cut through the centre of flesh, "John this is all part of my research! And Mrs Hudson doesn't mind it one bit." John's face turned red, "Mrs Hudson doesn't bloody live with you!"

As they arrived, Natasha could hear the commotion coming from the apartment. "I'll join you shortly and that will explain itself." The employer watched as Natasha stepped out of the car, knocking on the door. An older lady answered the door, "Hello I'm Mrs Hudson, the land lady, and you're here for Sherlock I figure." Natasha wondered if everyone that knocked on the door was looking for Sherlock, "Yes Ma'am, could you direct me to his room?" She followed the lady up the stairs straight to the door. She could hear yelling coming from inside.

"Sherlock dear, you have a visitor." Mrs Hudson opened the door and Sherlock jumped over the couch, "Not now Mrs Hudson I'm working!" Startled, the old lady walked back down stairs. "Get off the lounge Sherlock!" John waved his hands in the air, not noticing the red head standing in the doorway. Natasha Romanoff cleared her throat and both men turned to her. "I apologise in advance. Yes he is normally like this. And yes it is completely normal. I'm Dr. - " Natasha moved past the doctor toward Sherlock. "Yes I know who you are Dr. John Watson. And you must be Sherlock Holmes." She gestured to the man kneeling next to the bookshelf. John was puzzled, "How do you know my name, and what exactly are you doing here?" Natasha smiled, genuinely, for the mans puzzled face.

Mycroft chuckled, walked in and sat down on one of the arm chairs. John spun around, "And what are _you _doing here Mycroft?" With a cup of tea in his hand Mycroft gleamed, "Well, I have hired Miss Romanoff here to protect you and Sherlock."

Sherlock still kneeled next to the bookshelf, hastily flicking through a book, "Could you all please be quite, I'm trying to think." Mycroft sipped his tea and crossed his leg over the other. "Now, now Sherlock. We have a guest, be kind." Sherlock groaned like a child and rolled to his feet, walking over to the lady standing in his apartment. Looking her up and down, he began his observation much to the dismay of John, "Born in Russia, specifically Stalingrad, where _one _of your last names descended. You are a highly trained spy, martial arts expert and quite the adequate sniper." Sherlock paced to Natasha's side, "Eventually you defected to the US. A love interest I'm presuming. But he is a colleague, so it is complicated. Your parents were killed in a fire. You are lean and fit. You're agile, most likely a ballet dance when you were younger. You were also a test subject for the super soldier experimental serum, and because of that the white blood cells in your body can fight of any disease or microbe. You appear to have never been sick in your life." Sherlock turned to Mycroft, "Why would John and I possibly need a bodyguard?" Mycroft sipped his tea and looked at Natasha. Sherlock lifted an eyebrow and John still stood confused. Poor thing. Natasha stepped up to Sherlock leaning in close to his face, "You are insensitive and constantly mocked for being eccentric. You hear the words 'piss off' a lot don't you? You care more about the crime than the victim. Claim to be married to work. Disdained of love or affection. You can play violin, and you are a smoker, or do the nicotine patches simply help you think? Just discovered coffee, the bags under your eyes tell me that. You are overly but not obviously protective of John. Yes. I know a bit about you Sherlock, and you label yourself a Consulting Detective. And a high functioning sociopath. Obviously." Sherlock stared at this woman, her red curls a little frizzled from the rain outside, her full lips smiled in triumph. Mycroft giggled, enjoying the show. John gave Sherlock a pat on the back, "I like her already."


End file.
